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Estimation on dynamic release of phosphorus from wind-induced suspended particulate matter in Lake Taihu

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Science China Earth Sciences 2004年第8期47卷 710-719页

作者： FAN Chengxin1. ZHANG Lu1.2. QIN Boqiang1. WANG Sumin1. HU Weiping1.& ZHANG Chen1.1. Taihu Lake Laboratory for Ecosystem Research, Nanjing Institute of Geography & Limnology, chinese Academy of Sciences, Nanjing 2.0}008, China 2. Graduate School of chinese Academy of Sciences, Beijing 1.0039, China 1. Taihu Lake Laboratory for Ecosystem Research Nanjing Institute of Geography & Limnology Chinese Academy of Sciences 210008 Nanjing China 2. Graduate School of chinese Academy of Sciences 100039 Beijing China

Through man-made disturbance experiments, the corresponding relationships be-tween suspended particulate matter (SPM) and wind speed in different lake areas were simu-lated, the physicochemical formal transformation and biological mineralizing and decaying processes of phosphorus in SPM were studied, the contribution of phosphorus transformation to phosphorus loading of the water of Lake Taihu was quantitatively estimated. The results show that about 0.44 t·a-1.loading in Lake Taihu mainly comes from phosphorus-releasing action of SPM in physicochemical transformed to soluble reactive phosphorus (SRP), and the contribution mainly from biological mineralizing and decaying was about 42..8 t·a-1. which is equal to 1..0% of the total external loading of Lake Taihu, namely 4.7—7.5 times as much as SRP loading en-tering the lake by the rivers; thus it is the important source in dynamical internal loading of the lake. The determining factors for dynamical internal loading in lakes are organic phosphorus content in suspended solid and its biological transition availability.

关键词： phosphorus release,wind wave disturbance,particulate decaying,dynamical loading,Lake Taihu.

Study of the circulation theory of the cooling system in vertical evaporative cooling generator

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Science China(Technological Sciences) 2006年第3期49卷 358-364页

作者： YU Shunzhou1. CAI Jing2. GUO Chaohong1.& GU Guobiao1.1. Institute of Electrical Engineering, chinese Academy of Sciences, Beijing 1.0080, China 2. Beijing Changcheng Institute of Metrology and Measurement, Beijing 1.0095, China Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100080 China Beijing Changcheng Institute of Metrology Measurement Beijing 100095 China

The article briefly states the current development of evaporative cooling generator; its advantages comparing with generators of traditional cooling. Vertical evaporative cooling generator, which adopts Close-Loop-Self-Cycle with no-pump; free convection boil in the hollow stator bar, is one of the great developments in generator design. This article emphasizes the importance of cooling system in generator; expatiates the circulation theory in two aspects, energy; flow;; analyzes the essential reason, motivity; stability of Close-Loop-Self-Cycle. The article points out that the motivity of the circulation is the heat absorbed by coolant. After absorbing heat the coolant will have the ability of doing work because of the phase change. In another words, it is the buoyancy causing by density difference leads to the Close-Loop-Self-Cycle. This conclusion is validated by experimental data.

关键词： vertical evaporative cooling generator, cooling system, circulation theory.

Detecting forest landscape boundary between Mountain Birch and evergreen coniferous forest in the northern slope of Changbai Mountain

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Journal of Environmental Sciences 2003年第2期15卷 182-186页

作者： CHANG Yu+1. BU Ren-cang+1. HU Yuan-man+1. XU Chong- gang+1. WANG Qing-li+2.(1. Institute of Applied Ecology, chinese Academy of Sciences, Shenyang 1.001., China. 2. Shenyang Branch, CAS) Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Shenyang Branch CAS Shenyang China

Boundaries between different forest types in Changbai Mountain Eastern China are results from complex interactions between forest ecosystems, topography, and geomorphology. Detecting and quantifying the transitional zones are highly important since high environmental heterogeneity and biodiversity are often found within these zones. In this study, we used GIS and multivariate statistics techniques(PCA and MSWA) to analyze data from Landsat TM satellite imageries and quantitatively determined the positions and widths of the landscape boundary between mountain birch and evergreen coniferous forests in the northern slope of Changbai Mountain. The results showed that the widths of the landscape boundary ranges from 30—50m while using the MSWA or/and PC method. Such detected widths are consistent with field transect data that suggests a 50m transitional zone width. The results further suggest that TM data can be used in combination with GIS and statistical techniques in determining forest landscape boundaries; MSWA is more reliable than PCA, while PCA can also be used to determine the landscape boundary when transects are properly located.

关键词： Changbai Mountain forest landscape boundary PCA & MSWA

Ecological rebuilding and land reclamation in surface mines in Shanxi Province, China

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Journal of Environmental Sciences 2000年第4期12卷 486-497页

作者： MIAO Ze wei 1. BAI Zhong ke 2. GAO Lin 1.(1. Research Center for Eco Environmental Sciences, chinese Academy of Sciences, Beijing 1.0085, China E\|mail: miaozewei@*** 2. Department of Soil Science, Shanxi Agricultural University Taigu, 03 中科院生态环境研究中心北京 1 0 0 0 85 山西师范大学山西临汾 0 3 0 80 1

It is well known that the mining industry produces a large amount of derelict land, and causes pollution of water loss and soil erosion as well as other environmental damage in China. As land is under pressure in China, it is now policy to restore or reclaim land despoiled by mining, the aim being to develop sustainable and healthy arable land ecosystems. This paper outlines the principles and approaches of ecological restoration, which have been adopted in Shanxi Province with reference to three typical surface mines. In the research, the principles of ecological engineering and ecological succession are considered as the critical theories of ecological restoration in mine degraded land. Meanwhile, the paper made a comparative research on main links of ecological rebuilding in three surface mines in Shanxi Province, which include new land construction, treatment of toxic substances, control of soil erosion, fertility management, irrigation, ecological planning and the establishment of legislation systems. As the research demonstrated, for successful restoration, new land construction is the fundamental framework, but it must be integrated with ecological engineering including ecological planning, the control of soil erosion and vegetation establishment and ecosystem creation in order to optimise land productivity and soil fertility. In addition, the establishment of the legislation systems and organization of administration are also indispensable aspects of ecological rebuilding in mined land.

关键词： ecological restoration land reclamation open-pit mine

Jinning granodiorite and diorite deeply concealed in the central Tarim Basin

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Science China Earth Sciences 2005年第12期48卷 2061-2068页

作者： LI Yuejun1. 2. SONG Wenjie2. WU Genyao1. WANG Yifen1. LI Yuping2.& ZHENG Duoming2.1. Institute of Geology & Geophysics, chinese Academy of Sciences, Beijing 1.002., China 2. Tarim Oil-field Company, PetroChina, Korla 841.00, China 1. Institute of Geology & Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Tarim Oil-field Company 841000 Korla PetroChina China

The 72.0-m-deep Well Tacan 1.in the central Tarim Basin is the deepest in China. Purplish gray medium-grained granodiorite containing dark gray fine-grained diorite xenolith is revealed at the base of the well (71.9―72.0 m), and they are results of the Jinning magmatic activities. Trace-element geochemistry and REE profiles of both rock types are similar, indicating that they are calc-alkaline series I-type granitoid. Proxies of diorite signify the development of a magmatic arc due to subduction at ca. 1.00 Ma. The granodiorite was formed before 890―932.Ma. However, more study is needed to clarify if the arc diorite represents a ca. 300 Ma extension of the subduction or a reactivation during the orogenic collision event at ca. 900 Ma.

关键词： diorite, granodiorite, magmatic arc, Jinning orogeny, Tarim Basin.

Comparison of temporal and Spatial Characteristics of Ozone Pollution at Ground Level in the Eastern China

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chinese Journal of Population,Resources and Environment 2006年第3期4卷 51-57页

作者： Liu Houfeng1.2.1. Shandong Normal University, Jinan 2.001., China 2. chinese Research Academe of Environmental Sciences, Beijing 1.001., China Shandong Normal University Jinan 250014 China chinese Research Academe of Environmental Sciences Beijing 100012 China

Monitoring data from ozone（O3） automatic stations in three typical cities with different climatic areas in the southern and northern parts of eastern China are used to analyze temporal and spatial characteristics of ozone pollution at ground level. The results show that ozone pollution level has distinct regional differences and the concentration in the suburbs is higher than that in the urban areas. The seasonal variation of ozone concentration in different climatic areas is greatly affected by the variation of precipitation. Ozone concentration in Shenyang and Beijing , in the temperate zone, has one perennial peak concentration, occurring in early summer, May or June. Ozone concentration in Guangzhou, in sub-tropical zone, has two peak values year round. The highest values occur in October and the secondary high value in June. The ozone season in the south is longer than that in the north. The annual average daily peak value of ozone concentrations in different climates usually occur around 3 pm. The diurnal variation range of ozone concentration declines with the increase of latitude. Ozone concentration does not elevate with the increase of traffic flow. Ozone concentration in Guangzhou has a distinct reverse relation to CO and NOx. This complicated non-linearity indicates that the equilibrium of ozone photochemical reaction has regional differences. Exceeding the rate of Beijing＇s lh ozone concentration is higher than that of Guangzhou, whereas the average 8h ozone level is lower than that of Guangzhou, indicating that areas in low latitude are more easily affected by moderate ozone concentrations and longer exposure. Thus, China should work out standards for 8h ozone concentration.

关键词： ozone temporal and spatial characteristics 8h concentrations weekly variation

Evaluation criteria for gas source rocks of marine carbonate in China

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Progress in Natural Science:Materials International 2005年第9期15卷 810-817页

作者： WANG Zhaoyun1.*, ZHAO Wenzhi1.and WANG Yunpeng2.1. Research Institute of Petroleum Exploration & Development,PetroChina, Beijing 1.0083, China 2. Guangzhou Institute of Geochemistry, chinese Academy of Sciences, Guangzhou 51.640, China) Research Institute of Petroleum Exploration & Development PetroChina Beijing 100083 China. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Hydrocarbon generating and expulsion simulation experiments are carried out using samples artifically matched between the acid-dissolved residue of relatively low-maturity limestone and the original sample. This work makes up for the insufficiency of source rock samples with high abundance of organic matters and low maturity in China. The organic carbon content of the 1. prepared samples varies between 0.1.% and 0.74%. Pyrolysis data and simulation experiment results of hydrocarbon generating and expulsion, which were obtained by a high-temperature and high-pressure open system, indicate that the lower limit of organic carbon content for marine carbonate rock to generate and expel hydrocarbons is 0.2.%—0.31.. In combination with the numerical analysis of organic carbon in marine carbonate rocks from Tarim Basin, Sichuan Basin, Ordos Basin and North China, as well as the contribution of these gas source rocks to the discovered gas pools, we think that the organic carbon criterion for carbonate gas source rocks should be 0.3%.

关键词： carbonate gas source rock gas-generating efficiency evaluation criteria simulation experiment.

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归一化模型在人类认知活动中的应用

应用心理学 2024年

作者：孙阳阳罗鑫宇周柳芳李海燕孙彦良 1.山东师范大学心理学院 2.上海外国语大学国际工商管理学院 3.山东大学齐鲁医院神经外科山东师范大学心理学院上海外国语大学国际工商管理学院山东大学齐鲁医院神经外科

神经计算模型是深入解析神经元信息编码过程的重要方法。近年来，归一化模型(normalization model)作为一种新兴神经计算方法，在人类认知活动中广泛应用。此模型基于当前反应神经元的活动与神经元池活动总和的比率，来揭示神经元的实... 详细信息

神经计算模型是深入解析神经元信息编码过程的重要方法。近年来，归一化模型(normalization model)作为一种新兴神经计算方法，在人类认知活动中广泛应用。此模型基于当前反应神经元的活动与神经元池活动总和的比率，来揭示神经元的实际响应。最初用于解析初级视觉皮层中的神经元活动，随后在感知觉和注意机制研究中得到了充分的验证和应用，但在高级认知活动研究中的应用仍显不足。展望未来，归一化模型在高级认知活动研究中的应用值得进一步拓展。

关键词：归一化模型感觉注意决策工作记忆

Relationship between surface subsidence factor and mining depth of strip pillar mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 594-598页

作者： GUO Wen-bing1. 2. HOU Quan-lin 1. ZOU You-feng2.1. College of Earth Science, Graduate University of chinese Academy of Sciences, Beijing 1.0049, China 2. School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China chinese Acad Sci Coll Earth Sci Grad Univ Beijing 100049 Peoples R China Henan Polytech Univ Sch Energy Sci & Engn Jiaozuo 454000 Peoples R China

Strip pillar mining is one of the most important technical measures to control mining subsidence in China. Mining depth is one of the most important factors that can affect the mining subsidence in strip pillar mining. Six numerical simulation models were set up to simulate the surface subsidence of strip pillar mining in different mining depths. The mining depth in these six models ranges from 300 to 800 m. The simulated results were compared and analyzed. The formula was established based on the simulated results. It demonstrated that the subsidence of strip pillar mining method is related to mining depth. While the other conditions are the same, the subsidence of strip pillar mining increases with the increase of mining depth by logarithmic relationship.

关键词： subsidence factor strip pillar mining mining depth numerical simulation